Process of raising the calorific value of liquid fuel



Patented Nov. 19, 1935 PROCESS OF RAISING THE CALORIFIC VALUE OF LIQUID FUEL Alexander Glassen, Aachen, Germany No Drawing.

Application February 21, less,-

Serial No. 657,845. In Germany July so, 1932 2 Claims. (01. 44-9) Attempts have been made for a long time to disperse coal in petroleum, so as to obtain a stable suspension which can be used as a fuel instead of pure petroleum. Apart from the fact that up to now it hasbeen practically impossible to make mixtures in which the coal would not rapidly deposit, the use of coal for the said purpose has big disadvantages. First of all, it must be mentioned that coal contains considerable amounts of ash producing substances, which produces difllculties when petroleum-coal mixtures are used in the usual machines designed for pure petroleum firing.

It is now found that the calorific value of liquid fuels can be raised in an appreciably better fashion if products rich in carbon and ob-.

' tained from wood are incorporated in them in a finely divided state. In this way, stable suspensions are obtained together with a series of other important advantages. Among the latter are to be found the fact that products rich in carbon and obtained from wood produce little or no ash and, as a consequence, burn without leaving a residue; by mixing the added materials in accordance with the invention, practically no increase in volume is obtained; lastly, the use of fuels made in accordance with the invention brings about an extraordinary cheapening of the relatively costly liquid-fuels.

In addition to finely divided coal, lignin which is obtained in large quantities in the known processes forthe saccharificatlon of wood as well as in processes for obtaining furfurol from materials containing cellulose can also be used as an 35 additional substance. This lignin, which remains as a finely divided insoluble powder, when, for example, the cellulose is dissolved in highly concentrated hydrochloric acid to an amount of 25-30% according to the nature of the starting materials used, was hitherto hardly usable. Its use for the purpose in question here thus solves two problems at the same time.

In addition/to the products rich in carbon and obtained from wood which have already been mentioned, finely divided, more or less pure amorphous carbon can also be dispersed in fuels, which leads to a particularly important increase in the calorific value of the fuel obtained. Lignin may, for example, be used for obtaining the amorphous carbon and for this purpose be treated in the following fashion.

The lignin obtained, for example, in the mentioned process for the sacohariflcation of wood is washed with water, dried at about 100 and is subjected to dry distillation at a low temperature.

. Combustible gases are given off which can be used for various purposes and if desired can be used as sources of heat for the dis-integrating process.

A residue is produced which is a loose, porous mass consisting of amorphous carbon. 5

Instead of lignin, other organic materials rich in carbon and preferably of high molecular weight, for example, organic acids or substances of high molecular weight derived from them such, for instance, as glucose obtained in the saccharification'of wood and in certain cases cane sugar or molasses can be treated in a similar fashion to produce the amorphous carbon.

The carbon obtained can be easily very finely subdivided and in this form suspended in liquid fuels without giving rise to any separation especially at low temperatures. It will be understood that several of the above mentioned products rich in carbon can be suspended at the same time in liquid fuels and thus, for example, finely divided wood charcoal can be used in addition to amorphouscarbon.

As the dispersing medium, known fuels and especially petroleum or products obtained from it such as benzine and the like and benzene or alcohols such as butyl alcohol can also be used.

Furfurol can also be used as a dispersing medium, which according to earlier researches of the inventor, can be used for the driving of intemal combustion engines.

Lastly, mixtures of fuels can be used such as benzine-benzene mixtures, mixtures of benzine, benzene and furfurol or mixtures of benzine, hen-- acne and alcohol.

If necessary, small amounts of materials for increasing the stability of colloidal systems can be added in the known manner to the mixtures.

The fuel mixtures according to the invention which may contain very substantial amounts of products richin carbon, for example, 25-50% or more of the mixtures, can be used in any way in .which the usual fuels are used. In general, it is not necessary to make any alterations to the burning devices such as burners, carburettors 'and the like.

Example 1. Equal volumes of benzine and benzene are mixed and 25, or if need be, up to-% or more of colloidal carbon is suspended in this mixture, the calorific value of which is to be raised.

2. Equal volumes of benzine and benzene are mixed, one volume of furfurol added to this mixture and again 25, 30' or if need be up to 50% zine and three parts the parts by volume 0! benot benzene, one part of a mixture of 3 5 butyl alcohol is added-which, for example, has

been obtained from need be up to 50% or is again suspended in glucose and 25, 30 or if more of colloidal carbon the mixture. I

I claim:

1. Al bustion iquid fuel suitable for use in internal comengines, consisting essentially o1 furrurol and a colloidal, substantially pure amor phous carbon obtained by the dry distillation of lignin, dispersed and suspended therein.

2. A method 01' increasing the calorific value of liquid fuels, which comprises forming a pure amorphous carbon by the dry distillation of lignin, and incorporating such amorphous carbon in finely divided form in a liquid hydrocarbon fuel containing Iurfurol.

ALEXANDER CLASSEN. 

